HP Z4 G4 and GPU with 2x8-pin power-connectors

[Jukkisss]

Dear HP support forum,

I must ask about an issue which has been already present on some occasions, but I'm still unsure about this. Simply: Can I, without issues, install a more powerful GPU with 2x8-pin power-input connectors to my computers PSU 2x6-pin power connectors, using adapter cables? An example of this cable is:

Deltaco Adapterikaapeli 6-pin PCI-E > 8-pin PCI-E2, 10 cm - Jimms.fi

My current setup is as below, purchased as a whole unit from a dealer, and it's working great, also under heavy gaming and GPU-use.

HP Z4 G4 with 750W power supply (with 2x6-pin GPU power connectors, one used to the GPU, one free to use)

Xeon processor

Nvidia RTX 2060 Super 8GB model (with 1x8-pin power connector input connected to one PSU 6-pin connector using adapter, like in the link).

Issues / contradictory information, which make me unsure, in random order:

- I have come to understanding, that the HP 750W PSU 6-pin connectors each can provide more wattage in comparison to the standard 6-pin ATX-standard connector

- Also, there are recommendations to only use HP-official 6-pin to 8-pin adapter-cables. Is my current GPU-power connection okay?

- When using 3rd-party "6-pin to 8-pin" adapters, like in the link, can these adapters handle the greater wattage coming to the 6-pin connector from PSU?

- Also, I have seen posts and recommendations to use "Dual 6-pin to Single 8-pin / Y-cable" adapter cables to connect two PSU 6-pin connectors to one GPU 8-pin connector to "provide necessary" power to the GPU. In that regard, my current setup is not properly done?

- Also, in this Youtube video (https://www.youtube.com/watch?v=s5KhWCuqZ2s) GPU with 2x8pin power-input is connected to 1x6-pin PSU-cable using "single-6-pin to dual 8-pin" adapter cable. I assume that better way would be to utilize both 6-pin PSU connectors with two individual "6-pin to 8-pin" adapters, as in my current plan?

Sorry for the long post. I really appreciate the help. 

Kind regards,
Jukkiss

[SDH · Accepted solution]

Welcome to our friend in Finland.

Some basics... you can look at the HP QuickSpecs for your workstation, latest you can find, to see the max wattage HP has certified for your Z4 G4. Other video cards of same wattage or even a reasonable amount more usually are fine. There may be notes in the QuickSpecs such as power supply requirement to use the higher wattage video cards. Here in the US we have pretty easy access to recycled power supplies and other HP parts via eBay. Not sure about Finland. I'd want have the highest power HP power supply available which you appear to. I will answer your questions in order, from under your "Issues" section.

1. Yes that is true. You can find the labels on any HP workstation power supply and see the Amperage each supplemental video power circuit is rated for and multiply that by 12VDC to get Watts. That is quite a bit higher than the ATX standard for a PCIe supplemental power cable (which is only 75W). The HP PCIe x16 workstation video slots now virtually always give 75W up to the card each. Each HP workstation supplemental graphics cable now virtually always gives 18A. See here:

Yours...

2. I'd not say "only" but would say it is a darn good idea because HP engineered these adapters specifically for this purpose.  However those can be hard to find and there have been some sold that were stated to be from HP but were not. If you look at the genuine ones you can see the HP label and ferrite core HP adds for noise suppression, HERE .

3. Some can and some can't. I've seen cheap very poor quality ones that even had some of the 8-pin plug end holes empty. The metal connectors in those holes can be non-standard thin metal with poor fit, resulting in significant heat build up and even melting of plastic/insulation. The wires can be thin and floppy and not proper for a higher wattage power draw, Proper jumper wires to populate all holes may be absent. One non-HP version I've seen that is good quality is from StarTech, PCIEX68ADAP, HERE.  I'd still prefer HP's 6-to-8 adapter over all else. The one you show might be fine, however.

4. No you don't need to combine your two HP power supply's 6-pin plug ends into one 8-pin plug end for powering a Nvidia RTX 2060 Super 8GB (which is rated for 175W max power draw). Do the math in #1 above and don't forget to add in the 75W from  your motherboard's PCIe3 x16 video slot.

5. HP does not offer a single 6-pin to dual 8-pin adapter and they know what they're doing. I would not advise to do that.

[Jukkisss]

Many thanks, SDH, that you had time to write me a thorough and fast response. I will make a note of your five points for future reference. Marked as solved.